Why would anyone think Hawkeye would even come within spitting distance of a court or legal proceeding, period? There's no need to convince a DA or jury of *anything*, because he's not going to be tried, or arrested, in the first place. Never mind that the analogies to drunk driving are utterly, laughably fallacious.

Put bluntly, if SHIELD is fine with employing Black Widow, who actually *was* a willing murderer for hire, they are not going to kick Hawkeye out for being mind controlled.